Crane



Jan. 13, 1953 G. M. BA-BARE ET AL CRANE Filed July 5, 1951 m TE m Mb a E E T U E E E T E m B 5 n E h D R illjllll l l li lllll ATTORNEY Patented Jan. 13, 1953 UNITED STATES PATENT OFFICE CRANE George Martin Babare andRobert StBabare, Tacoma, Wash.

3 Claims. 1

This invention relates to improvements in cranes, particularly designed for'logging purposes,

but not necessarily limited tothis use.

In logging, heavy machinery. is. employed, ,particularly where large logs are'handled. "With the heavy and expensive machinery ordinarily used in the operation it does not pay to pick up the small logs to transport them to the mill. From the standpoint of economy, the smaller logs are either left behind, or picked up later on with the use of less expensive machinery.

The usual cranes used in logging operations are not only heavy and clumsy to handle, but they involve cables, drums and other elements, and are not adapted for small operations.

The prime object of this invention is to provide a simple, inexpensive crane which can be conveniently manipulated, and mounted on a truck and hauled through the woods to the lighter and small logs, to pick up the latter, and deliver them to the platform for transportation.

We are aware this broad idea is old in the art, but such cranes have mechanical as well as economic drawbacks.

A further object of the invention is to provide a crane wherein the boom is mounted directly on the shaft, in this instance a screw, and braced to, and by the screw shaft, thus dispensing with the use of cables and other complicated accessories used on ordinary cranes employed for loging operations.

A further object of the invention is to provide a boom associated with a screw shaft, whereby the boom can be raised and lowered and braced by said screw shaft.

A still further object of the invention is to provide a crane, wherein the raising and lowering means serves as the locking means to hold the boom in supported position and at the same time provides means whereby the boom may be rotated. thrust of the boom is against the screw shaft.

A still further object of the invention is to provide a boom, wherein, when carryin a load, the thrust of the boom is against the screw shaft, which in turn is transmitted to a supporting standard, a brace being so connected between the In the drawings:

Fig. 1 is aperspective view of the improved crane.

Fig. 2 is a side elevation showing the beam in an extended position in full linesand the beam elevated in dottedlines.

I indicates a base, and rising therefrom is a standard 2. A bearing 3 is formed in the base, and in vertical alignment therewith in the top of the standard is a bearing t, and extending from the standard and in alignment with the bearings d and 5 is an intermediate bearing 5. Mounted in the bearings 3, 4 and 5 is a vertical shaft 6 having right and left hand threads '1 and 8.

A nut 9 is mounted on the upper threads I, and a nut I0 is mounted on the lower threads 8. Pivoted to the lower nut I0 is a boom l2, and pivoted to the boom at I3 is a brace l4 pivoted to the upper nut 9 at 15.

Secured to the lower end of the shaft is a worm gear It, and meshin with thi gear is a worm I! mounted on a power shaft [8 on the base I. Of course, the power shaft will be controlled by suitable reversing mechanism and other necessary adjuncts (not shown) to regulate the movement of the shaft.

In operation, the power shaft [8 is operated, and through the medium of the gears, the screw shaft is rotated, and the boom is elevated, as shown in Fig. 1. Suppose when the boom is in position carrying a log, and it is desired to swing the load around to deliver it, movement of the power shaft is stopped, and the boom can be readily manually rotated and at the same time the load is held suspended, save the slight movement of the nuts on the threads.

While the load is suspended, the screw shaft takes the thrust incident to the connection oi the lower portion of the boom with the lower nut and the connection of the brace with the intermediate portion of the boom and the upper nut. In other words, the weight or load carried by the free overhanging end of the boom sets up a bracing or balancing action against the screw shaft and through the latter to the standard. The brace M thus acts to take the strain between the upper end of the load and the boom, while the brace It and the boom form a toggle connection between the screw shaft and the boom, and yet while the load is suspended the boom is locked or held supported by the screw shaft.

To lower the boom the power shaft is operated to rotate the screw shaft in the opposite direction.

In this action the upper nut 9 is lowered by the threads 1 and simultaneously the lower nut In is raised by the lower threads 8.,

At any stage or position of the boom, the latter can be radially manually turned to deliver the load to a platform.

The construction is simple and the parts are so arranged a substantially strong and durable structure is provided for raising, lowering and rotating a load from a pick-up to delivery position.

What we claim is:

1. A logging crane comprising a base, a standard rising therefrom, upper and intermediate bearings on the standard, a bearing on the base, a shaft mounted in the bearings, right and left hand threads formed on the shaft, a nut engaging the lower threads, a nut engaging the upper threads, a boom pivoted to the lower nut, a brace pivoted at one end intermediate the boom and pivoted at its upper end to the nut engaging the upper threads, and gears at the lower end of the shaft to rotate same, whereby when the shaft is rotated, one way, the boom will be elevated in a direction toward the shaft and when the movement of the shaft is reversed the boom will be lowered in a direction away from the shaft.

2. A logging crane, comprising a standard, a vertical shaft mounted on the standard, right and left hand threads formed on the vertical shaft, a nut engaging the lower threads, a nut engaging the upper threads, a boom pivoted to the lower nut, and a brace pivoted at one end intermediate the boom and pivoted at its upper end to the nut engaging the upper threads, movement-of the nuts on the shaft when rotated rocking the boom toward 01' away from the shaft and its outer end up or down to raise or lower a load carried by the boom.

3. A logging crane, as defined in claim 2, wherein the shaft is supported by upper, lower and intermediate bearings provided on the standard.

GEORGE MARTIN BABARE. ROBERT S. BABARE.

REFERENCES CITED UNITED STATES PATENTS Name Date Sawyer Nov. 15, 1892 Number 

